1. Field of the Invention
This invention relates to therapeutic beds and especially to such beds which are adapted to both tilt and vibrate in order to provide treatment of circulatory problems.
2. Description of Related Art
It has been known for many years to employ oscillatory motion in the treatment of back, spine and muscle ailments. For instance, U.S. Pat. No. 835,622, issued Nov. 13, 1906, to Kellogg, shows a movement cure apparatus comprising a seat or chair mounted on resilient feet. A shaft is supported by the seat with a weight mounted on the shaft together with means for adjusting the weight. U.S. Pat. No. 1,797,306, issued Mar. 24, 1931, to Webb, shows a massaging and vibrating machine having a rectangular framework adapted to support in a resilient manner a framework having a tautly stretched member thereon. A rotatable shaft with unbalanced weights fixedly mounted to it is secured for rotation on the resiliently mounted framework and a motor is connected to the shaft to produce vibrations. U.S. Pat. No. 2,674,993, issued Apr. 13, 1954, to Harrell, shows a vibrating board comprising a rectangular base member and an electric motor rigidly attached to the bottom of the base member. The motor has eccentrics on its shaft for producing vibrations in the board. Straps are attached to the top of the board for holding a person.
Furthermore, beds have been suggested which include tilting or bending portions to provide a more comfortable position for a person to lie in. Also, the change in position has therapeutic value. U.S. Pat. No. 1,037,419, issued Sept. 3, 1912, to Bosanko, shows two angularly movable pairs of arms operative to raise and support a bed spring and a hand crank operative to move the arms. Adjustable stops are connected to the side rails of the spring with each pair of arms carrying devices that lie under and fit up against the side rails of the frame. U.S. Pat. No. 3,611,453, issued Oct. 12, 1971, to Lokken, shows an invalid bed and tilt actuating mechanism comprising a pair of scissor arms wherein movement of the frame is effected by buckling of the scissors upon which a patient supporting frame rests. Buckling is normally prevented by at least one butterfly arm pivotally carried by one longitudinal member of the patient supporting frame. U.S. Pat. No. 3,802,002, issued Apr. 9, 1974, to Jonas, shows a hospital bed in which the legs at each end of the bed are connected by a cross member so that the legs can pivot together to adjust the height of the bed from the floor. U.S. Pat. No. 3,997,926, issued Dec. 21, 1976, to England, shows a bed with automatic occupant tilting support. The England bed comprises an elongated leg supported framework and a flat rigid occupant support platform mounted for pivotal movement between a horizontal position and an upright position. A screw shaft is connected between a nut pivotally mounted to the framework and a bracket mounted to the underside of the occupant support platform.
Finally, beds have also been suggested which include tilting devices and vibration producing mechanisms. One example of such a bed can be seen in U.S. Pat. No. 3,042,025, issued July 3, 1962, to Jackson. The Jackson apparatus includes an elongated sectional and foldable frame in which the sections are hingedly joined for movement between extended and folded positions. The frame provides, when extended, an elevated intermediate portion and a downwardly inclined portion extending from the elevated portion so as to rest upon a floor or other surface. A device for vibrating the frame is carried by the elevated portion.